impl<'a, 'tcx, T> Decodable<DecodeContext<'a, 'tcx>> for LazyArray<T> {
fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Self {
let len = decoder.read_usize();
- if len == 0 { LazyArray::empty() } else { decoder.read_lazy_array(len) }
+ if len == 0 { LazyArray::default() } else { decoder.read_lazy_array(len) }
}
}
.tables
.children
.get(self, index)
- .unwrap_or_else(LazyArray::empty)
+ .expect("fields are not encoded for a variant")
.decode(self)
.map(|index| ty::FieldDef {
did: self.local_def_id(index),
.tables
.children
.get(self, item_id)
- .unwrap_or_else(LazyArray::empty)
+ .expect("variants are not encoded for an enum")
.decode(self)
.filter_map(|index| {
let kind = self.def_kind(index);
.tables
.fn_arg_names
.get(self, id)
- .unwrap_or_else(LazyArray::empty)
+ .expect("argument names not encoded for a function")
.decode((self, sess))
.nth(0)
.map_or(false, |ident| ident.name == kw::SelfLower)
.tables
.children
.get(self, id)
- .unwrap_or_else(LazyArray::empty)
+ .expect("associated items not encoded for an item")
.decode((self, sess))
.map(move |child_index| self.local_def_id(child_index))
}
fn get_associated_item(self, id: DefIndex, sess: &'a Session) -> ty::AssocItem {
let name = self.item_name(id);
- let kind = match self.def_kind(id) {
- DefKind::AssocConst => ty::AssocKind::Const,
- DefKind::AssocFn => ty::AssocKind::Fn,
- DefKind::AssocTy => ty::AssocKind::Type,
+ let (kind, has_self) = match self.def_kind(id) {
+ DefKind::AssocConst => (ty::AssocKind::Const, false),
+ DefKind::AssocFn => (ty::AssocKind::Fn, self.get_fn_has_self_parameter(id, sess)),
+ DefKind::AssocTy => (ty::AssocKind::Type, false),
_ => bug!("cannot get associated-item of `{:?}`", self.def_key(id)),
};
- let has_self = self.get_fn_has_self_parameter(id, sess);
let container = self.root.tables.assoc_container.get(self, id).unwrap();
ty::AssocItem {
.tables
.children
.get(self, id)
- .unwrap_or_else(LazyArray::empty)
+ .expect("fields not encoded for a struct")
.decode(self)
.map(move |index| respan(self.get_span(index, sess), self.item_name(index)))
}
.tables
.children
.get(self, id)
- .unwrap_or_else(LazyArray::empty)
+ .expect("fields not encoded for a struct")
.decode(self)
.map(move |field_index| self.get_visibility(field_index))
}
.tables
.inherent_impls
.get(self, id)
- .unwrap_or_else(LazyArray::empty)
.decode(self)
.map(|index| self.local_def_id(index)),
)
.tables
.inherent_impls
.get(self, ty_index)
- .unwrap_or_else(LazyArray::empty)
.decode(self)
.map(move |impl_index| (ty_def_id, self.local_def_id(impl_index)))
})
) -> DefPathHash {
*def_path_hashes
.entry(index)
- .or_insert_with(|| self.root.tables.def_path_hashes.get(self, index).unwrap())
+ .or_insert_with(|| self.root.tables.def_path_hashes.get(self, index))
}
#[inline]
use crate::creader::{CStore, LoadedMacro};
use crate::foreign_modules;
use crate::native_libs;
+use crate::rmeta::table::IsDefault;
use crate::rmeta::AttrFlags;
use rustc_ast as ast;
}
}
};
+ ($tcx:ident, $def_id:ident, $other:ident, $cdata:ident, $name:ident => { table_defaulted_array }) => {
+ provide_one! {
+ $tcx, $def_id, $other, $cdata, $name => {
+ let lazy = $cdata.root.tables.$name.get($cdata, $def_id.index);
+ if lazy.is_default() { &[] } else { $tcx.arena.alloc_from_iter(lazy.decode(($cdata, $tcx))) }
+ }
+ }
+ };
($tcx:ident, $def_id:ident, $other:ident, $cdata:ident, $name:ident => { table_direct }) => {
provide_one! {
$tcx, $def_id, $other, $cdata, $name => {
}
provide! { tcx, def_id, other, cdata,
- explicit_item_bounds => { table }
+ explicit_item_bounds => { table_defaulted_array }
explicit_predicates_of => { table }
generics_of => { table }
- inferred_outlives_of => { table }
+ inferred_outlives_of => { table_defaulted_array }
super_predicates_of => { table }
type_of => { table }
variances_of => { table }
symbol_table: FxHashMap<Symbol, usize>,
}
-/// If the current crate is a proc-macro, returns early with `LazyArray::empty()`.
+/// If the current crate is a proc-macro, returns early with `LazyArray::default()`.
/// This is useful for skipping the encoding of things that aren't needed
/// for proc-macro crates.
macro_rules! empty_proc_macro {
($self:ident) => {
if $self.is_proc_macro {
- return LazyArray::empty();
+ return LazyArray::default();
}
};
}
}
}
-// Shorthand for `$self.$tables.$table.set($def_id.index, $self.lazy_value($value))`, which would
+// Shorthand for `$self.$tables.$table.set_some($def_id.index, $self.lazy_value($value))`, which would
// normally need extra variables to avoid errors about multiple mutable borrows.
macro_rules! record {
($self:ident.$tables:ident.$table:ident[$def_id:expr] <- $value:expr) => {{
{
let value = $value;
let lazy = $self.lazy(value);
- $self.$tables.$table.set($def_id.index, lazy);
+ $self.$tables.$table.set_some($def_id.index, lazy);
}
}};
}
-// Shorthand for `$self.$tables.$table.set($def_id.index, $self.lazy_value($value))`, which would
+// Shorthand for `$self.$tables.$table.set_some($def_id.index, $self.lazy_value($value))`, which would
// normally need extra variables to avoid errors about multiple mutable borrows.
macro_rules! record_array {
+ ($self:ident.$tables:ident.$table:ident[$def_id:expr] <- $value:expr) => {{
+ {
+ let value = $value;
+ let lazy = $self.lazy_array(value);
+ $self.$tables.$table.set_some($def_id.index, lazy);
+ }
+ }};
+}
+
+macro_rules! record_defaulted_array {
($self:ident.$tables:ident.$table:ident[$def_id:expr] <- $value:expr) => {{
{
let value = $value;
{
let def_key = self.lazy(table.def_key(def_index));
let def_path_hash = table.def_path_hash(def_index);
- self.tables.def_keys.set(def_index, def_key);
+ self.tables.def_keys.set_some(def_index, def_key);
self.tables.def_path_hashes.set(def_index, def_path_hash);
}
} else {
for (def_index, def_key, def_path_hash) in table.enumerated_keys_and_path_hashes() {
let def_key = self.lazy(def_key);
- self.tables.def_keys.set(def_index, def_key);
+ self.tables.def_keys.set_some(def_index, def_key);
self.tables.def_path_hashes.set(def_index, *def_path_hash);
}
}
let on_disk_index: u32 =
on_disk_index.try_into().expect("cannot export more than U32_MAX files");
- adapted.set(on_disk_index, self.lazy(source_file));
+ adapted.set_some(on_disk_index, self.lazy(source_file));
}
adapted.encode(&mut self.opaque)
if state.is_doc_hidden {
attr_flags |= AttrFlags::IS_DOC_HIDDEN;
}
- if !attr_flags.is_empty() {
- self.tables.attr_flags.set_nullable(def_id.local_def_index, attr_flags);
- }
+ self.tables.attr_flags.set(def_id.local_def_index, attr_flags);
}
fn encode_def_ids(&mut self) {
let def_id = local_id.to_def_id();
let def_kind = tcx.opt_def_kind(local_id);
let Some(def_kind) = def_kind else { continue };
- self.tables.opt_def_kind.set(def_id.index, def_kind);
+ self.tables.opt_def_kind.set_some(def_id.index, def_kind);
let def_span = tcx.def_span(local_id);
record!(self.tables.def_span[def_id] <- def_span);
self.encode_attrs(local_id);
record!(self.tables.generics_of[def_id] <- g);
record!(self.tables.explicit_predicates_of[def_id] <- self.tcx.explicit_predicates_of(def_id));
let inferred_outlives = self.tcx.inferred_outlives_of(def_id);
- if !inferred_outlives.is_empty() {
- record_array!(self.tables.inferred_outlives_of[def_id] <- inferred_outlives);
- }
+ record_defaulted_array!(self.tables.inferred_outlives_of[def_id] <- inferred_outlives);
}
if should_encode_type(tcx, local_id, def_kind) {
record!(self.tables.type_of[def_id] <- self.tcx.type_of(def_id));
record!(self.tables.trait_impl_trait_tys[def_id] <- table);
}
}
+
let inherent_impls = tcx.with_stable_hashing_context(|hcx| {
tcx.crate_inherent_impls(()).inherent_impls.to_sorted(&hcx, true)
});
-
- for (def_id, implementations) in inherent_impls {
- if implementations.is_empty() {
- continue;
- }
- record_array!(self.tables.inherent_impls[def_id.to_def_id()] <- implementations.iter().map(|&def_id| {
+ for (def_id, impls) in inherent_impls {
+ record_defaulted_array!(self.tables.inherent_impls[def_id.to_def_id()] <- impls.iter().map(|def_id| {
assert!(def_id.is_local());
def_id.index
}));
};
record!(self.tables.variant_data[variant.def_id] <- data);
- self.tables.constness.set(variant.def_id.index, hir::Constness::Const);
+ self.tables.constness.set_some(variant.def_id.index, hir::Constness::Const);
record_array!(self.tables.children[variant.def_id] <- variant.fields.iter().map(|f| {
assert!(f.did.is_local());
f.did.index
}));
if let Some((CtorKind::Fn, ctor_def_id)) = variant.ctor {
- self.tables.constness.set(ctor_def_id.index, hir::Constness::Const);
+ self.tables.constness.set_some(ctor_def_id.index, hir::Constness::Const);
let fn_sig = tcx.fn_sig(ctor_def_id);
record!(self.tables.fn_sig[ctor_def_id] <- fn_sig);
// FIXME only encode signature for ctor_def_id
fn encode_explicit_item_bounds(&mut self, def_id: DefId) {
debug!("EncodeContext::encode_explicit_item_bounds({:?})", def_id);
let bounds = self.tcx.explicit_item_bounds(def_id);
- if !bounds.is_empty() {
- record_array!(self.tables.explicit_item_bounds[def_id] <- bounds);
- }
+ record_defaulted_array!(self.tables.explicit_item_bounds[def_id] <- bounds);
}
fn encode_info_for_trait_item(&mut self, def_id: DefId) {
let tcx = self.tcx;
let impl_defaultness = tcx.impl_defaultness(def_id.expect_local());
- self.tables.impl_defaultness.set(def_id.index, impl_defaultness);
+ self.tables.impl_defaultness.set_some(def_id.index, impl_defaultness);
let trait_item = tcx.associated_item(def_id);
- self.tables.assoc_container.set(def_id.index, trait_item.container);
+ self.tables.assoc_container.set_some(def_id.index, trait_item.container);
match trait_item.kind {
ty::AssocKind::Const => {}
ty::AssocKind::Fn => {
record_array!(self.tables.fn_arg_names[def_id] <- tcx.fn_arg_names(def_id));
- self.tables.asyncness.set(def_id.index, tcx.asyncness(def_id));
- self.tables.constness.set(def_id.index, hir::Constness::NotConst);
+ self.tables.asyncness.set_some(def_id.index, tcx.asyncness(def_id));
+ self.tables.constness.set_some(def_id.index, hir::Constness::NotConst);
}
ty::AssocKind::Type => {
self.encode_explicit_item_bounds(def_id);
let tcx = self.tcx;
let ast_item = self.tcx.hir().expect_impl_item(def_id.expect_local());
- self.tables.impl_defaultness.set(def_id.index, ast_item.defaultness);
+ self.tables.impl_defaultness.set_some(def_id.index, ast_item.defaultness);
let impl_item = self.tcx.associated_item(def_id);
- self.tables.assoc_container.set(def_id.index, impl_item.container);
+ self.tables.assoc_container.set_some(def_id.index, impl_item.container);
match impl_item.kind {
ty::AssocKind::Fn => {
let hir::ImplItemKind::Fn(ref sig, body) = ast_item.kind else { bug!() };
- self.tables.asyncness.set(def_id.index, sig.header.asyncness);
+ self.tables.asyncness.set_some(def_id.index, sig.header.asyncness);
record_array!(self.tables.fn_arg_names[def_id] <- self.tcx.hir().body_param_names(body));
// Can be inside `impl const Trait`, so using sig.header.constness is not reliable
let constness = if self.tcx.is_const_fn_raw(def_id) {
} else {
hir::Constness::NotConst
};
- self.tables.constness.set(def_id.index, constness);
+ self.tables.constness.set_some(def_id.index, constness);
}
ty::AssocKind::Const | ty::AssocKind::Type => {}
}
if let Some(trait_item_def_id) = impl_item.trait_item_def_id {
- self.tables.trait_item_def_id.set(def_id.index, trait_item_def_id.into());
+ self.tables.trait_item_def_id.set_some(def_id.index, trait_item_def_id.into());
}
if impl_item.kind == ty::AssocKind::Fn {
record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
- if tcx.is_intrinsic(def_id) {
- self.tables.is_intrinsic.set_nullable(def_id.index, true);
- }
+ self.tables.is_intrinsic.set(def_id.index, tcx.is_intrinsic(def_id));
}
}
match item.kind {
hir::ItemKind::Fn(ref sig, .., body) => {
- self.tables.asyncness.set(def_id.index, sig.header.asyncness);
+ self.tables.asyncness.set_some(def_id.index, sig.header.asyncness);
record_array!(self.tables.fn_arg_names[def_id] <- self.tcx.hir().body_param_names(body));
- self.tables.constness.set(def_id.index, sig.header.constness);
+ self.tables.constness.set_some(def_id.index, sig.header.constness);
}
hir::ItemKind::Macro(ref macro_def, _) => {
- if macro_def.macro_rules {
- self.tables.is_macro_rules.set_nullable(def_id.index, true);
- }
+ self.tables.is_macro_rules.set(def_id.index, macro_def.macro_rules);
record!(self.tables.macro_definition[def_id] <- &*macro_def.body);
}
hir::ItemKind::Mod(ref m) => {
}
hir::ItemKind::OpaqueTy(ref opaque) => {
self.encode_explicit_item_bounds(def_id);
- if matches!(opaque.origin, hir::OpaqueTyOrigin::TyAlias) {
- self.tables.is_type_alias_impl_trait.set_nullable(def_id.index, true);
- }
+ self.tables
+ .is_type_alias_impl_trait
+ .set(def_id.index, matches!(opaque.origin, hir::OpaqueTyOrigin::TyAlias));
}
hir::ItemKind::Impl(hir::Impl { defaultness, constness, .. }) => {
- self.tables.impl_defaultness.set(def_id.index, *defaultness);
- self.tables.constness.set(def_id.index, *constness);
+ self.tables.impl_defaultness.set_some(def_id.index, *defaultness);
+ self.tables.constness.set_some(def_id.index, *constness);
let trait_ref = self.tcx.impl_trait_ref(def_id).map(ty::EarlyBinder::skip_binder);
if let Some(trait_ref) = trait_ref {
let trait_def = self.tcx.trait_def(trait_ref.def_id);
if let Ok(mut an) = trait_def.ancestors(self.tcx, def_id) {
if let Some(specialization_graph::Node::Impl(parent)) = an.nth(1) {
- self.tables.impl_parent.set(def_id.index, parent.into());
+ self.tables.impl_parent.set_some(def_id.index, parent.into());
}
}
}
let polarity = self.tcx.impl_polarity(def_id);
- self.tables.impl_polarity.set(def_id.index, polarity);
+ self.tables.impl_polarity.set_some(def_id.index, polarity);
}
hir::ItemKind::Trait(..) => {
let trait_def = self.tcx.trait_def(def_id);
}
if let hir::ItemKind::Fn(..) = item.kind {
record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
- if tcx.is_intrinsic(def_id) {
- self.tables.is_intrinsic.set_nullable(def_id.index, true);
- }
+ self.tables.is_intrinsic.set(def_id.index, tcx.is_intrinsic(def_id));
}
if let hir::ItemKind::Impl { .. } = item.kind {
if let Some(trait_ref) = self.tcx.impl_trait_ref(def_id) {
ty::Closure(_, substs) => {
let constness = self.tcx.constness(def_id.to_def_id());
- self.tables.constness.set(def_id.to_def_id().index, constness);
+ self.tables.constness.set_some(def_id.to_def_id().index, constness);
record!(self.tables.fn_sig[def_id.to_def_id()] <- ty::EarlyBinder(substs.as_closure().sig()));
}
self.hygiene_ctxt.encode(
&mut (&mut *self, &mut syntax_contexts, &mut expn_data_table, &mut expn_hash_table),
|(this, syntax_contexts, _, _), index, ctxt_data| {
- syntax_contexts.set(index, this.lazy(ctxt_data));
+ syntax_contexts.set_some(index, this.lazy(ctxt_data));
},
|(this, _, expn_data_table, expn_hash_table), index, expn_data, hash| {
if let Some(index) = index.as_local() {
- expn_data_table.set(index.as_raw(), this.lazy(expn_data));
- expn_hash_table.set(index.as_raw(), this.lazy(hash));
+ expn_data_table.set_some(index.as_raw(), this.lazy(expn_data));
+ expn_hash_table.set_some(index.as_raw(), this.lazy(hash));
}
},
);
let spans = self.tcx.sess.parse_sess.proc_macro_quoted_spans();
for (i, span) in spans.into_iter().enumerate() {
let span = self.lazy(span);
- self.tables.proc_macro_quoted_spans.set(i, span);
+ self.tables.proc_macro_quoted_spans.set_some(i, span);
}
- self.tables.opt_def_kind.set(LOCAL_CRATE.as_def_id().index, DefKind::Mod);
+ self.tables.opt_def_kind.set_some(LOCAL_CRATE.as_def_id().index, DefKind::Mod);
record!(self.tables.def_span[LOCAL_CRATE.as_def_id()] <- tcx.def_span(LOCAL_CRATE.as_def_id()));
self.encode_attrs(LOCAL_CRATE.as_def_id().expect_local());
let vis = tcx.local_visibility(CRATE_DEF_ID).map_id(|def_id| def_id.local_def_index);
def_key.disambiguated_data.data = DefPathData::MacroNs(name);
let def_id = id.to_def_id();
- self.tables.opt_def_kind.set(def_id.index, DefKind::Macro(macro_kind));
- self.tables.proc_macro.set(def_id.index, macro_kind);
+ self.tables.opt_def_kind.set_some(def_id.index, DefKind::Macro(macro_kind));
+ self.tables.proc_macro.set_some(def_id.index, macro_kind);
self.encode_attrs(id);
record!(self.tables.def_keys[def_id] <- def_key);
record!(self.tables.def_ident_span[def_id] <- span);
Linkage::Static => Some(LinkagePreference::RequireStatic),
}));
}
- LazyArray::empty()
+ LazyArray::default()
}
fn encode_info_for_foreign_item(&mut self, def_id: DefId, nitem: &hir::ForeignItem<'_>) {
match nitem.kind {
hir::ForeignItemKind::Fn(_, ref names, _) => {
- self.tables.asyncness.set(def_id.index, hir::IsAsync::NotAsync);
+ self.tables.asyncness.set_some(def_id.index, hir::IsAsync::NotAsync);
record_array!(self.tables.fn_arg_names[def_id] <- *names);
let constness = if self.tcx.is_const_fn_raw(def_id) {
hir::Constness::Const
} else {
hir::Constness::NotConst
};
- self.tables.constness.set(def_id.index, constness);
+ self.tables.constness.set_some(def_id.index, constness);
record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
}
hir::ForeignItemKind::Static(..) | hir::ForeignItemKind::Type => {}
}
if let hir::ForeignItemKind::Fn(..) = nitem.kind {
- if tcx.is_intrinsic(def_id) {
- self.tables.is_intrinsic.set_nullable(def_id.index, true);
- }
+ self.tables.is_intrinsic.set(def_id.index, tcx.is_intrinsic(def_id));
}
}
}
type Value<'tcx> = LazyArray<T::Value<'tcx>>;
}
+impl<T> Default for LazyArray<T> {
+ fn default() -> LazyArray<T> {
+ LazyArray::from_position_and_num_elems(NonZeroUsize::new(1).unwrap(), 0)
+ }
+}
+
impl<T> LazyArray<T> {
fn from_position_and_num_elems(position: NonZeroUsize, num_elems: usize) -> LazyArray<T> {
LazyArray { position, num_elems, _marker: PhantomData }
}
-
- fn empty() -> LazyArray<T> {
- LazyArray::from_position_and_num_elems(NonZeroUsize::new(1).unwrap(), 0)
- }
}
/// A list of lazily-decoded values, with the added capability of random access.
/// Define `LazyTables` and `TableBuilders` at the same time.
macro_rules! define_tables {
(
- - nullable: $($name1:ident: Table<$IDX1:ty, $T1:ty>,)+
+ - defaulted: $($name1:ident: Table<$IDX1:ty, $T1:ty>,)+
- optional: $($name2:ident: Table<$IDX2:ty, $T2:ty>,)+
) => {
#[derive(MetadataEncodable, MetadataDecodable)]
}
define_tables! {
-- nullable:
+- defaulted:
is_intrinsic: Table<DefIndex, bool>,
is_macro_rules: Table<DefIndex, bool>,
is_type_alias_impl_trait: Table<DefIndex, bool>,
attr_flags: Table<DefIndex, AttrFlags>,
+ def_path_hashes: Table<DefIndex, DefPathHash>,
+ explicit_item_bounds: Table<DefIndex, LazyArray<(ty::Predicate<'static>, Span)>>,
+ inferred_outlives_of: Table<DefIndex, LazyArray<(ty::Clause<'static>, Span)>>,
+ inherent_impls: Table<DefIndex, LazyArray<DefIndex>>,
- optional:
attributes: Table<DefIndex, LazyArray<ast::Attribute>>,
lookup_const_stability: Table<DefIndex, LazyValue<attr::ConstStability>>,
lookup_default_body_stability: Table<DefIndex, LazyValue<attr::DefaultBodyStability>>,
lookup_deprecation_entry: Table<DefIndex, LazyValue<attr::Deprecation>>,
- // As an optimization, a missing entry indicates an empty `&[]`.
- explicit_item_bounds: Table<DefIndex, LazyArray<(ty::Predicate<'static>, Span)>>,
explicit_predicates_of: Table<DefIndex, LazyValue<ty::GenericPredicates<'static>>>,
generics_of: Table<DefIndex, LazyValue<ty::Generics>>,
- // As an optimization, a missing entry indicates an empty `&[]`.
- inferred_outlives_of: Table<DefIndex, LazyArray<(ty::Clause<'static>, Span)>>,
super_predicates_of: Table<DefIndex, LazyValue<ty::GenericPredicates<'static>>>,
type_of: Table<DefIndex, LazyValue<Ty<'static>>>,
variances_of: Table<DefIndex, LazyArray<ty::Variance>>,
generator_kind: Table<DefIndex, LazyValue<hir::GeneratorKind>>,
trait_def: Table<DefIndex, LazyValue<ty::TraitDef>>,
trait_item_def_id: Table<DefIndex, RawDefId>,
- inherent_impls: Table<DefIndex, LazyArray<DefIndex>>,
expn_that_defined: Table<DefIndex, LazyValue<ExpnId>>,
unused_generic_params: Table<DefIndex, LazyValue<UnusedGenericParams>>,
params_in_repr: Table<DefIndex, LazyValue<BitSet<u32>>>,
// `DefPathTable` up front, since we may only ever use a few
// definitions from any given crate.
def_keys: Table<DefIndex, LazyValue<DefKey>>,
- def_path_hashes: Table<DefIndex, DefPathHash>,
proc_macro_quoted_spans: Table<usize, LazyValue<Span>>,
generator_diagnostic_data: Table<DefIndex, LazyValue<GeneratorDiagnosticData<'static>>>,
variant_data: Table<DefIndex, LazyValue<VariantData>>,
use std::marker::PhantomData;
use std::num::NonZeroUsize;
+pub(super) trait IsDefault: Default {
+ fn is_default(&self) -> bool;
+}
+
+impl<T> IsDefault for Option<T> {
+ fn is_default(&self) -> bool {
+ self.is_none()
+ }
+}
+
+impl IsDefault for AttrFlags {
+ fn is_default(&self) -> bool {
+ self.is_empty()
+ }
+}
+
+impl IsDefault for bool {
+ fn is_default(&self) -> bool {
+ !self
+ }
+}
+
+impl IsDefault for u32 {
+ fn is_default(&self) -> bool {
+ *self == 0
+ }
+}
+
+impl<T> IsDefault for LazyArray<T> {
+ fn is_default(&self) -> bool {
+ self.num_elems == 0
+ }
+}
+
+impl IsDefault for DefPathHash {
+ fn is_default(&self) -> bool {
+ self.0 == Fingerprint::ZERO
+ }
+}
+
/// Helper trait, for encoding to, and decoding from, a fixed number of bytes.
/// Used mainly for Lazy positions and lengths.
/// Unchecked invariant: `Self::default()` should encode as `[0; BYTE_LEN]`,
/// but this has no impact on safety.
-pub(super) trait FixedSizeEncoding: Default {
+pub(super) trait FixedSizeEncoding: IsDefault {
/// This should be `[u8; BYTE_LEN]`;
/// Cannot use an associated `const BYTE_LEN: usize` instead due to const eval limitations.
type ByteArray;
fn write_to_bytes(self, b: &mut Self::ByteArray);
}
+/// This implementation is not used generically, but for reading/writing
+/// concrete `u32` fields in `Lazy*` structures, which may be zero.
impl FixedSizeEncoding for u32 {
type ByteArray = [u8; 4];
fn write_to_bytes(self, b: &mut [u8;1]) {
use $ty::*;
b[0] = match self {
- None => 0,
+ None => unreachable!(),
$(Some($($pat)*) => 1 + ${index()},)*
}
}
}
// We directly encode `DefPathHash` because a `LazyValue` would incur a 25% cost.
-impl FixedSizeEncoding for Option<DefPathHash> {
+impl FixedSizeEncoding for DefPathHash {
type ByteArray = [u8; 16];
#[inline]
fn from_bytes(b: &[u8; 16]) -> Self {
- Some(DefPathHash(Fingerprint::from_le_bytes(*b)))
+ DefPathHash(Fingerprint::from_le_bytes(*b))
}
#[inline]
fn write_to_bytes(self, b: &mut [u8; 16]) {
- let Some(DefPathHash(fingerprint)) = self else {
- panic!("Trying to encode absent DefPathHash.")
- };
- *b = fingerprint.to_le_bytes();
+ debug_assert!(!self.is_default());
+ *b = self.0.to_le_bytes();
}
}
#[inline]
fn from_bytes(b: &[u8; 8]) -> Self {
let krate = u32::from_le_bytes(b[0..4].try_into().unwrap());
- let index = u32::from_le_bytes(b[4..8].try_into().unwrap());
if krate == 0 {
return None;
}
+ let index = u32::from_le_bytes(b[4..8].try_into().unwrap());
Some(RawDefId { krate: krate - 1, index })
}
#[inline]
fn write_to_bytes(self, b: &mut [u8; 8]) {
match self {
- None => *b = [0; 8],
+ None => unreachable!(),
Some(RawDefId { krate, index }) => {
// CrateNum is less than `CrateNum::MAX_AS_U32`.
debug_assert!(krate < u32::MAX);
#[inline]
fn write_to_bytes(self, b: &mut [u8; 1]) {
+ debug_assert!(!self.is_default());
b[0] = self.bits();
}
}
#[inline]
fn write_to_bytes(self, b: &mut [u8; 1]) {
+ debug_assert!(!self.is_default());
b[0] = self as u8
}
}
#[inline]
fn write_to_bytes(self, b: &mut [u8; 4]) {
- let position = self.map_or(0, |lazy| lazy.position.get());
+ match self {
+ None => unreachable!(),
+ Some(lazy) => {
+ let position = lazy.position.get();
+ let position: u32 = position.try_into().unwrap();
+ position.write_to_bytes(b)
+ }
+ }
+ }
+}
+
+impl<T> LazyArray<T> {
+ #[inline]
+ fn write_to_bytes_impl(self, b: &mut [u8; 8]) {
+ let ([position_bytes, meta_bytes],[])= b.as_chunks_mut::<4>() else { panic!() };
+
+ let position = self.position.get();
let position: u32 = position.try_into().unwrap();
- position.write_to_bytes(b)
+ position.write_to_bytes(position_bytes);
+
+ let len = self.num_elems;
+ let len: u32 = len.try_into().unwrap();
+ len.write_to_bytes(meta_bytes);
+ }
+
+ fn from_bytes_impl(position_bytes: &[u8; 4], meta_bytes: &[u8; 4]) -> Option<LazyArray<T>> {
+ let position = NonZeroUsize::new(u32::from_bytes(position_bytes) as usize)?;
+ let len = u32::from_bytes(meta_bytes) as usize;
+ Some(LazyArray::from_position_and_num_elems(position, len))
}
}
-impl<T> FixedSizeEncoding for Option<LazyArray<T>> {
+impl<T> FixedSizeEncoding for LazyArray<T> {
type ByteArray = [u8; 8];
#[inline]
fn from_bytes(b: &[u8; 8]) -> Self {
- let ([ref position_bytes, ref meta_bytes],[])= b.as_chunks::<4>() else { panic!() };
- let position = NonZeroUsize::new(u32::from_bytes(position_bytes) as usize)?;
- let len = u32::from_bytes(meta_bytes) as usize;
- Some(LazyArray::from_position_and_num_elems(position, len))
+ let ([position_bytes, meta_bytes],[])= b.as_chunks::<4>() else { panic!() };
+ if *meta_bytes == [0; 4] {
+ return Default::default();
+ }
+ LazyArray::from_bytes_impl(position_bytes, meta_bytes).unwrap()
}
#[inline]
fn write_to_bytes(self, b: &mut [u8; 8]) {
- let ([ref mut position_bytes, ref mut meta_bytes],[])= b.as_chunks_mut::<4>() else { panic!() };
+ assert!(!self.is_default());
+ self.write_to_bytes_impl(b)
+ }
+}
- let position = self.map_or(0, |lazy| lazy.position.get());
- let position: u32 = position.try_into().unwrap();
- position.write_to_bytes(position_bytes);
+impl<T> FixedSizeEncoding for Option<LazyArray<T>> {
+ type ByteArray = [u8; 8];
- let len = self.map_or(0, |lazy| lazy.num_elems);
- let len: u32 = len.try_into().unwrap();
- len.write_to_bytes(meta_bytes);
+ #[inline]
+ fn from_bytes(b: &[u8; 8]) -> Self {
+ let ([position_bytes, meta_bytes],[])= b.as_chunks::<4>() else { panic!() };
+ LazyArray::from_bytes_impl(position_bytes, meta_bytes)
+ }
+
+ #[inline]
+ fn write_to_bytes(self, b: &mut [u8; 8]) {
+ match self {
+ None => unreachable!(),
+ Some(lazy) => lazy.write_to_bytes_impl(b),
+ }
}
}
where
Option<T>: FixedSizeEncoding<ByteArray = [u8; N]>,
{
- pub(crate) fn set(&mut self, i: I, value: T) {
- self.set_nullable(i, Some(value))
+ pub(crate) fn set_some(&mut self, i: I, value: T) {
+ self.set(i, Some(value))
}
}
impl<I: Idx, const N: usize, T: FixedSizeEncoding<ByteArray = [u8; N]>> TableBuilder<I, T> {
- pub(crate) fn set_nullable(&mut self, i: I, value: T) {
- // FIXME(eddyb) investigate more compact encodings for sparse tables.
- // On the PR @michaelwoerister mentioned:
- // > Space requirements could perhaps be optimized by using the HAMT `popcnt`
- // > trick (i.e. divide things into buckets of 32 or 64 items and then
- // > store bit-masks of which item in each bucket is actually serialized).
- self.blocks.ensure_contains_elem(i, || [0; N]);
- value.write_to_bytes(&mut self.blocks[i]);
+ /// Sets the table value if it is not default.
+ /// ATTENTION: For optimization default values are simply ignored by this function, because
+ /// right now metadata tables never need to reset non-default values to default. If such need
+ /// arises in the future then a new method (e.g. `clear` or `reset`) will need to be introduced
+ /// for doing that explicitly.
+ pub(crate) fn set(&mut self, i: I, value: T) {
+ if !value.is_default() {
+ // FIXME(eddyb) investigate more compact encodings for sparse tables.
+ // On the PR @michaelwoerister mentioned:
+ // > Space requirements could perhaps be optimized by using the HAMT `popcnt`
+ // > trick (i.e. divide things into buckets of 32 or 64 items and then
+ // > store bit-masks of which item in each bucket is actually serialized).
+ self.blocks.ensure_contains_elem(i, || [0; N]);
+ value.write_to_bytes(&mut self.blocks[i]);
+ }
}
pub(crate) fn encode(&self, buf: &mut FileEncoder) -> LazyTable<I, T> {
let start = self.position.get();
let bytes = &metadata.blob()[start..start + self.encoded_size];
let (bytes, []) = bytes.as_chunks::<N>() else { panic!() };
- match bytes.get(i.index()) {
- Some(bytes) => FixedSizeEncoding::from_bytes(bytes),
- None => FixedSizeEncoding::from_bytes(&[0; N]),
- }
+ bytes.get(i.index()).map_or_else(Default::default, FixedSizeEncoding::from_bytes)
}
/// Size of the table in entries, including possible gaps.
}
}
+impl Default for DefPathHash {
+ fn default() -> Self {
+ DefPathHash(Fingerprint::ZERO)
+ }
+}
+
impl Borrow<Fingerprint> for DefPathHash {
#[inline]
fn borrow(&self) -> &Fingerprint {
hir::ItemKind::Impl(ref impl_) => tcx.arena.alloc_from_iter(
impl_.items.iter().map(|impl_item_ref| impl_item_ref.id.owner_id.to_def_id()),
),
- hir::ItemKind::TraitAlias(..) => &[],
_ => span_bug!(item.span, "associated_item_def_ids: not impl or trait"),
}
}
fn associated_items(tcx: TyCtxt<'_>, def_id: DefId) -> ty::AssocItems<'_> {
- let items = tcx.associated_item_def_ids(def_id).iter().map(|did| tcx.associated_item(*did));
- ty::AssocItems::new(items)
+ if tcx.is_trait_alias(def_id) {
+ ty::AssocItems::new(Vec::new())
+ } else {
+ let items = tcx.associated_item_def_ids(def_id).iter().map(|did| tcx.associated_item(*did));
+ ty::AssocItems::new(items)
+ }
}
fn impl_item_implementor_ids(tcx: TyCtxt<'_>, impl_id: DefId) -> FxHashMap<DefId, DefId> {